27 Systemic Mycoses 1 Flashcards
Endemic mycoses share some features. These are? (6, review more than memorize)
-In nature-In a geographic region-Inhale->lungs->dissemination-human-human transmission almost never occurs-often asymptomatic-healthy CAN be infected
A bronchoscopic biopsy grows mold 5 days after visiting California central valley. I’ve got fever, chest pain, cough, night sweats. What do I have?
Coccidioidomycosis
Doc, what will happen to me now that I’ve got coccidioidomycosis? (3)
-asymptomatic (60%)-valley fever that goes away on its own (30%)-progressive lung nodules or dissemination
How is coccidioidomycosis diagnosed? (4)
-spherules on wet prep-BIOHAZARD for lab (like all dimorphics)-IgM or IgG in serum are useful for those NOT in endemic areas-hyphae w/ alternating barrel-shaped arthroconidia
coccidioidomycosis treatment?
usually not needed
A chimney sweep or a bat cave explorer comes to you w/ pneumonia symptoms. What is it?
histoplasmosis
Histoplasmosis pathogenesis?
inhale microconidia/spores ->budding yeasts in body -> get yeasts in macrophages (or disseminates by bloodstream)
Histoplasmosis symptoms?
-95% asymptomatic-Lung: either self-limited, or chronic cavitary fibrosing mediastinitis-Systemic: sepsis in immunocompromised
Histoplasmosis diagnosis?
-BIOHAZARD dimorphic: Giemsa stain & see yeast both extracellular and inside macrophages. (look like acorns)-Urine antigen test BEST
African histoplasmosis is caused by what organism?
histoplasma capsulatum var. duboisii
How is African histoplasmosis different than normal histoplasmosis?
-Larger, thick-walled yeast-Get giant cells-Less pulmonary involvement, but more bone/skin problems.
Histoplasmosis treatment?
Usually none. For severe: amphotericin B
Wisconsin! (or EAST U.S.) Lung, skin, & bone lesions, what fungus?
Blastomycosis[broad based budding!]
Blastomycosis is asymptomatic in what %?
1/2 (so high virulence for a fungus) (it can turn chronic in some!)
Blastomycosis diagnosis involves what?
-BIOHAZARD dimorphic. Wet prep, culture (which takes 4 wks!), or ELISA for exoantigen A.-Broad-Based Budding & lollipops coming off the hyphae!
Blastomycosis treatment?
-Amphotericin B (or others, the point is you actually DO treat this fungus)
I’ve got fever, cough, nodular lung lesions, painful ulcerated oro-labial lesion. Rarely my disease disseminates. I just came from Guatemala. What do I have?
Paracoccidioidomycosis “South American Blasto”
I look like a pilot’s wheel on wet prep. What am I? Should I be treated?
-paracoccidioidomycosis.-Yes
I’ve got a rash on face, lymphadenopathy, palpable spleen tip, bilateral chest x-ray infiltrate. HIV positive, and I came from Vietnam. What do I have?
Penicillium marneffei [think HIV in SouthEast Asia! Soil and bamboo rats.]
What does Penicillium marneffei look like on stain?
elliptical yeast form w/ fission septae. red. (dimorphic beware!!)
Penicillium marneffei treatment?
amphotericin B
I rolled in pigeon poo. I’ve got pulmonary problems, MENINGITIS, fatigue, somnolence, HIV, mental status changes, and you see encapsulated yeast on india ink prep as well as a positive polysaccharide antigen test in CSF (BEST test) as well as mucoid yeast colonies that grew on GMS stain. What do I have?
Cryptococcus neoformans (C. gatii if the pigeon lived in a eucalyptus tree)[think meningitis in HIV patient! It it’s NOT an HIV patient, it’s C. gatii)
What antibiotic is used for life for prophylaxis of some fungi for immunocompromised?
fluconazole
What antibiotic is used for really bad fungal infections?
amphotericin B
